Step 1: Log into cPanel.
Step 2: Navigate to the Email section.
Step 3: Select the Email Accounts icon.
Step 4: Scroll down to the email address for which you need to update the quota resources.
Step 5: Next to the desired email address, click Change Quota.
Step 6: Either type in the new quota amount or select the Unlimited option.
Step 7: Click Change Quota.
Step 8: Once you have completed the above steps, the changes will be implemented immediately.